This polygon theme contains a spatial representation of Oregon's 2004/2006 Integrated Report on water quality, including the list of water quality limited waters needing TMDLs (303d List).The theme should be used in conjunction with the line theme ORStreamsWaterQuality_0406.shp and also Oregon's 2004/2006 Integrated Report. It was revised in January 2008, with each record in the data attribute table represented by a polygon feature.

Purpose:

This layer was developed to spatially display water bodies and information about water quality in those waters.

Time_Period_of_Content:

Time_Period_Information:

Single_Date/Time:

Calendar_Date: 2007

Currentness_Reference: Approved by EPA and effective February 26, 2007

Spatial Data: Water bodies without geospatial information are assigned placeholder LLIDs and are included in the data attribute table. The river mile at the Oregon border in some cases is corrected to the river mile from the mouth of the water body outside of Oregon. Streamlines are projected through bay, estuary, lake and reservoir shapes.

Line work representing lakes were reselected from StreamNet 1:100,000 river reach data files for Oregon for water body segments identified in Oregon's 2004/2006 Integrated Report on water quality. Out of the StreamNet reach data sets ONLY those features in the 2004/2006 Integrated Report are represented in this layer. The attribute scheme was revised for the lakes layer to present the information contained in the 2004/2006 Integrated Report records. Changes (additions, removals, modifications) were made to the GIS layers as needed to represent the 2004/2006 Integrated Report information. In the case of the Klamath and Lost rivers, the linework was extended beyond the state boundary to facilitate processing. River mile calculation was based on the direction of stream flow and determination of the beginning and ending point of the line segments.

Number derived from the latitude and longitude at the mouth of the water body or center of a lake/reservoir

Attribute_Definition_Source: StreamNet

Attribute:

Attribute_Label: STATUS

Attribute_Definition:

An assessment category assigned to each record based on evaluating water quality information
using the assessment methodology decision rules. Includes:
Category 2: Attaining - Some of the pollutant standards are met. (Status key = 1, 12).
Category 3: Insufficient data to determine whether a standard is met. (Status key = 6, 13).
Category 3B: Insufficient Data, Potential concern - Some data indicate non-attainment of a criterion,
but data are insufficient to assign another category. (Status key = 2, 19).
Category 4: Water is water quality limited but a TMDL is not needed because:
4A: TMDL approved - TMDLs needed to attain applicable water quality standards
have been approved. (Status key = 4,14).
4B: Other pollution control requirements are expected to address all pollutants and will
attain water quality standards. (Status key = 15).
4C: Impairment is not caused by a pollutant (e.g., flow or lack of flow is not considered a
pollutant.) (Status key = 7,16).
Category 5: Water is water quality limited and a TMDL is needed, Section 303(d) list.
(Status key = 3, 17).